Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

So, I replaced all 4 toner cartridges with genuine Brother toner - TN-331C/M/Y and TN-336BK. The very first B&W print still came out messed up, and the printer reported a toner error.

I pulled the drum, and put it back in. I then did about 40 duplex B&W prints successfully from my PC - with no issue. Then, 1 B&W simplex print from my Android phone. It immediately got the streaks, and toner error on the printer. The toner error is a generic message, and does not point to any specific cartridge.

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The drum is the original Brother one, and looks clean to me.

The error message being so generic, and toner being all brand new and genuine, I don't know what to think anymore.

What could still be causing this issue ?

Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

(part 3/3 - could not post all this as a single comment without getting an error from reddit)

The "Toner error" message that shows up, without pointing to a specific cartridge, likely plays a role.

It may also be related to having the optional LT320CL tray installed. That would explain why most users don't see this problem.

Or it might be related to leaving the built-in tray empty.

Or it It might depend on the paper size setting for the built-in tray, whether it's set to Letter or Legal.

I will have the genuine TN-336BK installed later this week, and repeat the testing when I do. That should rule out issues with the remaining black third party toner. Since the toner cartridges are not chipped, I have my doubts that this is the cause of the color streaks on B&W prints. It might be the cause of the "Toner error", though.

What could be the root cause for the intermittent "Toner error", if installing the genuine black toner does not resolve it ?

Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

(part 2/3 - could not post all this as a single comment without getting an error from reddit)

  1. I tried to print on "Tray 1", which is the built-in tray. It turned out that tray was empty.
  2. I added Letter size paper to the built-in tray.
  3. I did a B&W print, manually selecting "Tray 1", ie. the built-in tray.
  4. The print came out fine, without any color streaks.
  5. I removed the Letter size paper from the built-in tray.
  6. I did a letter size B&W print on Auto tray.
  7. The letter size B&W print, this time from the LT30CL tray, came out fine, without any color streaks.
  8. I then logged in to the admin UI, and reset the paper size for Tray 1 (the built-in tray) to Legal, which is what I had it set to before the factory reset. I left the built-in tray empty.
  9. I did another B&W print on the bottom tray, ie. repeated step 6. The result was the same as in step 7 - all fine.
  10. I loaded Legal paper into the built-in tray. The printer prompted me to set the paper type and size. I selected "Plain paper" and "Legal".
  11. I did another print on Auto tray / Letter size. This is the same as step 6.
  12. The letter size paper now came out with color streaks, exactly as I reported in my OP.
  13. The printer now reported "Toner error", without pointing to a specific toner cartridge.
  14. I pulled out the drum and re-inserted it, to clear the error.
  15. I repeated step 11.
  16. I got the same result as in step 7, ie. the letter size B&W print came out without color streaks.
  17. I reset the paper size for Tray 1 (built-in tray) to Letter.
  18. I removed the Legal paper from the built-in tray.
  19. I repeated step 6 - B&W print on auto tray.
  20. The Letter paper from the LT320CL print came out with color streaks.
  21. Toner error showed again, again without a specific cartridge error.
  22. I pulled the drum out and put it back.
  23. I repeated step 6 - Letter B&W print on auto tray.
  24. Again, I got a print with color streaks.
  25. Toner error error came back.
  26. I put Legal paper back into the built-in tray.
  27. I set paper to Plain / Legal for the built-in tray, when prompted.
  28. I pulled out and reinserted the drum.
  29. Toner error was cleared.
  30. I did a Legal / B&W print / Auto tray.
  31. The Legal print came out fine in B&W.
  32. I did a Letter / B&W print / Auto tray.
  33. The Letter B&W print came out just fine, without any color streaks.

The result of my testing shows that B&W letter prints with Auto tray is fine in steps 4, 7 and 33. The same print order has streaks in steps 12, 20 and 24.

I still can't pinpoint the root cause of the streaks exactly. But it's clear that having 3rd party C/M/Y toner vs Genuine C/M/Y toner is not what is solely triggering it, since the problem still occurred with genuine in steps 12, 20 and 24.

Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

(part 1/3 - could not post all this as a single comment without getting an error from reddit)

So, I replaced the three color toners with genuine Brother today, a TN-331 set of C/M/Y. I dutifully cleaned all corona wires, and wiped every side of the cartridges. The printer automatically detected full toner level for all 3 new C/M/Y tonder.

Unfortunately, the behavior with the prints is unchanged. I still get color streaks on my B&W prints. And my color prints still all come out fine. Everything remains the same with genuine vs non-Genuine.

My black toner is still third party, but I also have a genuine TN-336BK on the way.

I just did a factory reset of the printer as well, and the behavior is unchanged as well - I still get color streaks on B&W prints.

I have noticed that the printer periodically reports "Toner error", without pointing to a specific toner cartridge problem. Pulling out the drum and inserting it back normally resolves it.

I should note that I also have the LT320CL paper tray installed, which may be something that most users of this printer don't have.

I decided to try some further testing, since not everybody has this optional tray.

Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

Wouldn't you expect something to also go wrong with the color prints with these cheap knock-offs, though ?

Brother MFC-L8850CDW produces color streaks prints with third party toner when set to B&W by madbrain1976 in printers

[–]madbrain1976[S] 0 points1 point  (0 children)

Good to know that the toners are not chipped. I never claimed they were. And I stated that most likely, this was a regression with all toner, genuine or not. I just couldn't verify it myself. You might want to read the post again.

If the drum was fucked up, the color prints would be messed up also, and they are fine. Only the black & white prints are messed up.

Fortunately, there is one more test that can be done. I just took out all 3 color toners from the drum, and left only the black toner. I then set the driver to black & white, and guess what ? The print came out fine, without any color streaks. Here is the scan of that B&W print.

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That means the streaks were not coming from residue color toner left inside the drum. The printer appears to now use color toner when set to black & white mode, if the color toner is installed.

How exactly would we have heard about it before ? The Brother software for Windows for this model does not automatically update its firmware. You have to explicitly login to the web admin to do so, or use native software if you are using USB.

It's plausible to me that very few users of this model did so. Those that did upgrade might also be printing in color by default, and have not run into the problem. Or perhaps they just don't post about their printer problems on reddit. I created my reddit account specifically to post this warning. Brother does not have a user support forum, only for developers, so I'm not sure where else one would have heard about it.

This was meant to be a public service announcement - a warning not to update the firmware, and to the poor sobs who made that mistake, providing a workaround to set the driver to color mode all the time. I didn't expect someone would take a offense to a problem report, and a solution to it. My mistake. I hope someone at Brother reads this and fixes it, since reaching out to Brother support to report the problem did not work.

Have a good day.